It did indeed. I recently answered this question here.

This is an interesting question. In a word: Yes.

The phrase 'SOS' (a distress call still in modern day usage) was developed around the time of the sinking of the titanic, and the Titanic was one of the first to actually use the code between Morse Telegraphy operators.

Telegrams, and messages sent through telegraphy (I include Morse in this instance) were often charged (if you didn't have your own wire) per letter or per word. As a result, abbreviations of sentences into words, and words into letters, was widespread.

Even if you did have your own wire, because telegraphy was a 'poor' by modern standards form of communication (limited bandwidth; this is how much information you can send down the wire/radio, and not hugely powerful transmitters and receivers if by radio, or not very advanced circuits to amplify and decode the signal), you couldn't send a huge amount of letters down the line; it would take too long for the system/operator to type/tap them out, send them, and receive them.

In many instances, time was money. For example, if you were a stockbroker you'd want information quicker than others so you could make your trades for the most money. If you were a journalist with a newspaper, the only headline that matters is the first one; being the first to go to print on a big issue was hugely important for sales.

Interestingly, you could separate telegraphy abbreviations by both operator and 'client' applications. A client has to send the message and get meaning out of it, whilst the operator has to 'talk' with other operating stations to ensure the telegram gets to the right place. Both the message and the 'overhead' (words/letters/information used between operators to route the messages through the system etc) would be abbreviated.

In the instance of clients, Newspapers (and other organisations, once this caught on) would use the Phillips Code to relay information. This was an almost exhaustive list of abbreviations for things such as long words, common phrases, and proper nouns. We still use some of those today; POTUS is one such abbreviation.

With operator abbreviations, they would use them to signify things such as the start of a message, the end of a message, who the message is from and to, and various other purposes (like identifying yourself). There were numerous standardised codes across military, aviation, maritime, and land-based stations. 'Q Codes' were used for transmission-related information (like 'QC' meaning 'Is anyone out there to listen to me'), whilst others would be used to indicate specific instructions regarding a message ('92 codes' used a series of numbers to indicate things such as 'Are you ready (to receive a transmission)' or even 'Best Regards' and 'Love and Kisses' (either in messages or between operators talking to each other) ).

The legacy of these abbreviations is found in various places. Amateur Radio still uses them (for obvious reasons), but they've found themselves wormed into numerous places. Tx and Rx, in a technical capacity, are used to indicate Transmit and Receive signals in electronics, whilst Px may be used to indicate Passengers (on rail, boat, and plane), or Price (in cost of goods etc).